• 대한치과기공학회지
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• 제43권1호
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• pp.13-18
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• 2021

Purpose: This study aimed to compare the flexural properties and perform the Weibull analysis of photo-curing three-dimensional (3D) printing resin. Methods: Photo-curing temporary resin (3D polymer) was used as a printing resin. Specimens (65 × 10 × 3.3 ㎣) were prepared following the ISO 20975-1 guidelines and according to the different printing orientations using a digital light processing 3D printer (D2 120; Dentium). The flexural strength (FS), flexural modulus, and work of fracture (WOF) were measured using a universal testing machine (Instron 3344; Instron) at a crosshead speed of 5 mm/min. Results: In this study, the 0° orientation exhibited higher FS and WOF than the 45° orientation. Significant differences were found among the printing orientations (p<0.05). Specimens printed at the 0° orientation were the most accurate. In the Weibull analysis, 0° showed the greatest Weibull modulus (m), which represents a higher reliability. Conclusion: 3D printing should be selected and used by considering flexural properties, size accuracy, and reliability.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1394-1399
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• 2007

Recently, Study of 3D freeform fabrication method was working in the various applications. For example, in the powder base, it's laminated using a binding method or laser sintering method. However, these methods are not suitable in the office environments because it dust with powder that is bad for health. In this paper, we introduce a method of 3D freeform fabrication using a curing of photo-polymer resin and construct a system has multi printing head. A photo-polymer curing method has simply fabrication process and high strength of manufacturing part. However, this method has a problem on the multi print-head system. Because multi-printing system has a other printing method compare with a single printing system. Therefore, we experiment a single head 3D printing and proposed a 3D printing method using a multi-piezo head.

• 한국인쇄학회지
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• 제14권1호
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• pp.31-45
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• 1996

For the purpose of study on the printability of domestic art papers, the physical properties of domestic coated paper for offset printing were investigated. 25 kinds of sample papers were prepared and were examined in accordance with KS and TAPPI standard testing method i.e., basis weight, density, opacity, gloss, roughness, smoothness, brightness, and K&N absorption. IGT printability tester was used to obtain the printability parameters, such as maximum ink requirement of paper Y, limiting printing density D print through, and density smoothness constant m value.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.109-109
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• 2006

Screen printing (SP) metal contact is typically applied to the solar cells for mass production. However, SP metal contact has low aspect ratio, low accuracy, hard control of the substrate penetration and unclean process. On the other hand, photo lithograpy (PL) metal contact can reduce defects by metal contact. In this investigation, PL metal contact was obtained the multi-layer structure of Ti/Pd/Ag by e-beam process. We applied SP metal contact and PL metal contact to single crystalline silicon solar cells, and demonstrated the difference of conversion efficiency. Because PL metal contact silicon solar cell has Jsc (short circuit current density) better than silicon solar cell applied SP metal contact.

• 한국인쇄학회지
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• 제14권1호
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• pp.133-146
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• 1996

Eastman Kodak Co. has announced the concept of photo CD System in September, 1990 With Photo CD System technology, Kodak Co. Furnishes a convinent way to view, use and store photographic images. The heart of this system is a format provides progressively higher levels of image quality to meet the demands of NTSC, PAL and HDTV video displays as well as hard copy output. Also, image professionals are instrested in the capability of Photo CD, such as a way to store image at low cost in a high-resolution digital format that can be played back on different computer platforms. Many editors wish to use Photo CD images in the printing and publishing industry. However, Photo CD images were not processed detail enhancement and some others to use in the lithographic offset printing. Therefore, in this paper discribes a method to improve the sharpness of Photo CD images.

• 한국정밀공학회지
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• 제17권2호
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• pp.130-136
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• 2000

Generally, the build-up printed circuit board manufactured by the sequential process with etching, plating, drilling etc. requires many types of equipments and lead time. Etching process is suitable for mass production, however, it is not adequate for manufacturing prototype in the developing stage. In this study, we introduce a screen printing technology to prototyping a build-up printed circuit board. As for the material, photo/thermal curable resin and conductive paste are used for the formation of dielectric and conductor. The build-up structure is made by subsequent processes such as the formation of liquid resin thin layer, the solidification by UV/IR light, and via filling with conductive paste. By use of photo curable resin, productivity is greatly enhanced compared with thermal curable resin. Finally, the basic concept and the possibility of build-up printed circuit board prototyping are proposed in comparison with to the conventional process.

• 한국전기전자재료학회논문지
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• 제19권4호
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• pp.367-372
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• 2006

A carbon nanotube field emission display(CNT FED) panel with a 2 inch diagonal size was fabricated using a screen printing of a prepared photo-sensitive CNT paste and vacuum in-line sealing technology. After a surface treatment of the patterned CNT, only the carbon nanotube tips are uniformly exposed on the surface. The diameter of the exposed CNTs are usually about 20 nm. Using the photo-sensitive CNT paste, we have developed a triode type CNT FEA with a self-aligned gate-emitter structure. The turn on voltage was around 100 V which corresponds to according the turn on field of about $40V/{\mu}m$. By the creation of a self-aligned gate-emitter structure, it is expected that the screen printed photo-sensitive CNT paste is promising as a good candidate for the large size field emission display.

• 센서학회지
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• 제28권2호
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• pp.113-116
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• 2019

A three-dimensional porous structure was fabricated by pattern transfer printing for applications of electrodes in gas sensors. To form replica patterns, solutions were mixed with acetone, toluene, heptane, and poly(methyl methacrylate). These replica patterns can also be formed on substrates such as polyimide, polydimethylsiloxane, and silicon. The wide range of line widths from 1 to $5{\mu}m$ was derived from the surface grating patterns of master substrates. The cross-bar pattern with 40 layers showed a thickness of 600 nm. The area of platinum transferred patterns with different line widths was enhanced to $20{\times}25mm$, which is applicable to various electrode patterns of gas sensors.

• 한국산학기술학회논문지
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• 제9권1호
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• pp.202-213
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• 2008

본 연구에서는 디지털사진의 등장과 더불어 변화하는 시장 환경에 대응하기 위한 새로운 비즈니스 모델 구축을 위해 이용충족이론과 기술수용모델을 적용하여 소비자혁신성에 따른 디지털사진 이용동기와 디지털사진 인화서비스의 이용의도와의 관계모형과 가설을 설정하였다. 이에 대한 연구결과는 첫째, 혁신성과 이용동기와의 관계모형에서는 혁신성이 오락성, 사회성, 경제성에 정적인 영향력을 미치는 것으로 나타났다. 둘째, 혁신성과 이용의도와의 관계모형에서는 혁신성이 이용의도에 정적인 영향력을 미치는 것으로 나타났다. 셋째, 이용동기와 이용의도와의 관계모형에서는 편리성, 오락성, 경제성, 사회성이 이용의도에 정적인 영향력을 미치는 것으로 나타났다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.186-189
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• 2001

The main method in micro-etching process, used in manufacturing semiconductors, electronic components, circuits, is Photo Masking method that exposes and develops on the photo-sensitivity solutions or films. This method enables one to process highly precisely, $\pm$0.03 mm in end line location area. But this has limits in a high speed / wide width process, difficulties in endless masking, and the problem of high price. We have developed the direct masking method to make use of Gravure printing, widely used in grocery packing sheet printing. We made cylinder tools to influence the masking quality by laser stream process. We have confirmed that the end line location accuracy in the line width of the product is improved from 0.12 mm to $\pm$0.07 mm level, after etching process.